The present disclosure relates generally to an arrangement for, and a method of, accurately locating products associated with data to be captured by a mobile device, such as a handheld, mobile reader, in a noisy venue, such as a retail store, a factory, a warehouse, a distribution center, a building, or a like controlled area.
It is known to deploy a real-time ultrasonic locationing system in an indoor venue, such as a retail store, a factory, a warehouse, a distribution center, a building, or a like controlled area, to locate and to track a mobile device, such as a handheld data capture reader, a smartphone, a tablet, a computer, a smartwatch, or a like electronic device. A known ultrasonic locationing system includes an ultrasonic transmitter subsystem having a plurality of ultrasonic transmitters mounted at fixed, known locations spaced apart in the venue, each ultrasonic transmitter being operative, in its turn, for periodically transmitting ultrasonic ranging signals, e.g., ultrasonic pulses in the 20-22 kHz frequency range, to an ultrasonic receiver subsystem having a microphone mounted on, and jointly movable with, the mobile device. The ultrasonic locationing system locates the position, and tracks the movement, of the mobile device and, in turn, of the products having data being captured in a read zone of the mobile device, along a tracking path within the venue, typically by using differential flight time techniques known in the art that incorporate triangulation, trilateration, multilateration, and like locationing techniques.
Under ideal operating conditions, each transmitter periodically transmits the ranging signals along direct paths to the microphone, which receives the ranging signals in a quiet environment in which there is little or no ambient noise. The flight time difference between the transmit time at which each ranging signal is transmitted and the receive time at which each ranging signal is received along each direct path, together with the known speed of each ranging signal, as well as with the known locations of the transmitters, are used, among other factors, to determine the distance along each direct path, and, in turn, the position of the microphone mounted on the mobile device, and, in turn, the location of the mobile device, as well as the location of products having data being captured in a read zone of the mobile device.
However, in practice, the operating conditions of the known ultrasonic locationing system are typically less than ideal. Aside from the ranging signals being directed along non-direct, folded paths due to reflections and/or scattering and/or absorption by walls, the ceiling, the floor, curtains, windows, shelves, equipment, and myriad other objects or persons, in the venue, the venue is usually not a quiet environment, and the ambient noise level can sometimes be high enough to degrade the signal-to-noise ratio of the ultrasonic ranging signals. A low signal-to-noise ratio can lead to an erroneous determination of the location of the microphone and of the mobile device that carries the microphone and, in turn, of the products whose data is being captured by the mobile device.
Accordingly, it would be desirable to more accurately locate and track a mobile device and of the products whose data is being captured by the mobile device in a noisy venue by an ultrasonic locationing system.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and locations of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The arrangement and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.